<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=ul, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
    <style>
        *{
            padding:0;
            margin:0;
        }
        ul{
            width:200px;

        }
        li{
            width: 100px;
            height:100px;
            background:blue;
            display:inline-block;
        }
    </style>
</head>
<body>
    <ul>
        <li></li>
        <li></li>
        <li></li>
        <li></li>
    </ul>
</body>
</html>